feat: add plan-reviewer agent and plan-and-review skill for worker plan validation

[JeremyDev87]

Purpose

Workers in taskMaestro parallel execution currently go straight from PLAN to ACT without validating their plan. A dedicated plan-reviewer agent and plan-and-review skill would add a quality gate between PLAN and ACT, catching issues like invalid file paths, missing acceptance criteria, scope mismatch, and TDD gaps before any code is written.

Background

In the 2026-03-21 parallel execution session, workers occasionally produced suboptimal plans that led to rework during EVAL. A pre-ACT review step would reduce wasted iteration cycles.

Components

1. plan-reviewer Agent (specialist)

File: packages/rules/.ai-rules/agents/plan-reviewer.json

A specialist agent that reviews implementation plans before execution.

Review Checklist:

• Target file paths exist in the codebase (or are explicitly marked as "Create:")
• Acceptance criteria are specific, verifiable, and complete
• Scope matches issue specification (no over-engineering, no missing requirements)
• TDD approach applied where appropriate (test-first for logic, test-after for UI)
• Changes are backward-compatible or breaking changes are documented
• Estimated complexity matches actual scope (simple/medium/complex)

Output: Review result with severity-rated findings (Critical/High/Medium/Low)

2. plan-and-review Skill

File: packages/rules/.ai-rules/skills/plan-and-review/SKILL.md

Combines plan creation + automatic review in one workflow:

Phase 1: Create plan (using writing-plans methodology)
Phase 2: Dispatch plan-reviewer as subAgent
Phase 3: If Critical/High findings → revise plan → re-review
Phase 4: Plan approved → ready for ACT

3. Integration with parallel-orchestrator

Update worker AUTO mode prompt template to include:

PLAN 단계에서 plan-and-review 스킬을 사용하거나,
PLAN 완료 후 plan-reviewer를 subAgent로 파견하여 검증할 것.

Acceptance Criteria

• plan-reviewer.json agent definition created with review checklist
• plan-and-review/SKILL.md skill created with 4-phase workflow
• Agent validates: file paths, acceptance criteria, scope, TDD, backward compatibility
• Skill auto-dispatches plan-reviewer as subAgent after plan creation
• Critical/High findings trigger plan revision loop
• Clean pass → explicit "Plan Approved" signal
• README.md updated with new agent
• parallel-orchestrator worker prompt template references this skill

References

• Existing: technical-planner agent, writing-plans skill, executing-plans skill
• parallel-orchestrator: packages/rules/.ai-rules/agents/parallel-orchestrator.json
• Worker prompt template: parallel-orchestrator.json → workflow.worker_directive